Patent GB-706288-A (GB)
Title: Production of silicon-containing compounds
IPC: C07F7/04
Filed: 1952-04-28
Abstract: Polysilicates and orthosilicates having alkyl, cycloalkyl, aryl, alkaryl or aralkyl substituents are prepared by reacting anhydrous alcohols or phenols with a mixture consisting of silicon disulphide and a compound, possibly silicon oxysulphide, containing only silicon, oxygen and sulphur, which mixture is obtained by igniting silicon, silica and sulphur preferably in a molar proportion of 1:1:2.  The alcohols or phenols employed may have 1-18 carbon atoms such as methanol, ethanol, isopropanol, n p  butanol, tertiary butanol, n hexanol, n heptanol, 2 ethylhexanol, n octanol, lauryl or octadecyl alcohol, benzyl alcohol, 2 phenylethanol, or phenols such as phenol, cresol, p-ethylphenol, beta-naphthol or 2-hydroxy diphenyl.  The reaction of the phenol or alcohol may take place at ordinary or increased temperatures preferably under reflux, until the hydrogen sulphide evolution has ceased.  The reaction product, consisting of the orthosilicate and a mixture of polysilicates may be distilled or employed as such.  According to examples:-(1) ethyl alcohol was reacted with the mixture (silicon disulphide and silicon oxysulphide), refluxed for 2 hours and the residue washed with alcohol.  Fractionation of the combined filtrate and washings yielded tetraethyl orthosilicate, hexaethyl disilicate and octaethyl trisilicate. (2) the alcohol employed was 2 ethylhexanol, yielding tetrakis (2 ethylhexyl) orthosilicate, tetrakis (2 ethylhexyl) disilicate and octakis (2 ethylhexyl trisilicate.  (3) the mixture was finely ground and reacted with phenol in an iron retort 550 DEG C.  The unreacted phenol was removed by distillation and the residue removed from the retort and extracted with benzene.  Distillation yielded tetraphenyl orthosilicate and a polymeric material having a molecular weight of 930, probably a mixture of octa phenyl trisilicate and decaphenyl tetrasilicate.ALSO:Polysilicates and orthosilicates having alkyl, cycloalkyl, aryl, alkaryl or aralkyl substituents are prepared by reacting anhydrous alcohols or phenols with a mixture consisting of silicon disulphide and a compound, possibly silicon oxysulphide, containing only silicon, oxygen and sulphur, which mixture is obtained by igniting silicon, silica and sulphur preferably in a molar proportion of 1:1:2.  The alcohols or phenols employed may have 1-18 carbon atoms such as methanol, ethanol, isopropanol, n butanol, tertiary butanol, n-hexanol, n-heptanol 2-ethylhexanol, n-octanol, lauryl or octadecyl alcohol, benzyl alcohol, 2-phenyl-ethanol, or phenols such as phenol, cresol, p-ethylphenol, beta-naphthol or 2-hydroxy diphenyl.  The reaction of the phenol or alcohol may take place at ordinary or increased temperatures preferably under reflux, until the hydrogen sulphide evolution has ceased.  The reaction product, consisting of the orthosilicate and a mixture of polysilicates may be distilled or employed as such.  According to examples:-(1) Ethyl alcohol was reacted with the mixtures (silicon sulphide and silicon oxysulphide) refluxed for 2 hours and the residue washed with alcohol. Fractionation of the combined filtrate and washings yielded tetraethyl orthosilicate, hexaethyl disilicate and octaethyl trisilicate; (2) The alcohol employed was 2-ethylhexanol, yielding tetrakis (2-ethylhexyl) orthosilicate, hexakis (2-ethylhexyl) disilicate and octakis (2-ethylhexyl) trisilicate; (3) the mixture was finely ground and reacted with phenol in an iron retort at 550 DEG C.  The unreacted phenol was removed by distillation and the residue removed from the retort and extracted with benzene. Distillation yielded tetraphenyl orthosilicate and a polymeric material having a molecular weight of 930, probably a mixture of octaphenyl trisilicate and decaphenyl tetrasilicate.ALSO:Silicon, silica and sulphur, preferably in the molar proportion of 1 : 1 : 2 are ignited to prepare a mixture of silicon disulphide and a compound containing only silicon oxygen and sulphur, probably silicon oxysulphide or a cyclic thioether or a polymer of either.  The resulting mixture may be reacted with anhydrous alcohols and phenols (see Groups IV (a) and IV (b), 0.5 to 5 per cent. by weight of a heat-producing substance such as peroxide of barium, sodium or potassium may be incorporated before ignition which may be effected at 2000 DEG C. or above.  This temperature may be attained by thermite ignition (e.g. a mixture of aluminium and ferric oxide) in a fire-clay crucible.  The friable ignition product contains no elemental silicon and little silica.